Patch "crypto: x86/aes-ni - add missing error checks in XTS code" has been added to the 5.14-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    crypto: x86/aes-ni - add missing error checks in XTS code

to the 5.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     crypto-x86-aes-ni-add-missing-error-checks-in-xts-co.patch
and it can be found in the queue-5.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 766975526cd2b9c99375c6534ca3fefffd5965d1
Author: Ard Biesheuvel <ardb@xxxxxxxxxx>
Date:   Fri Jul 16 18:54:03 2021 +0200

    crypto: x86/aes-ni - add missing error checks in XTS code
    
    [ Upstream commit 821720b9f34ec54106ebf012a712ba73bbcf47c2 ]
    
    The updated XTS code fails to check the return code of skcipher_walk_virt,
    which may lead to skcipher_walk_abort() or skcipher_walk_done() being called
    while the walk argument is in an inconsistent state.
    
    So check the return value after each such call, and bail on errors.
    
    Fixes: 2481104fe98d ("crypto: x86/aes-ni-xts - rewrite and drop indirections via glue helper")
    Reported-by: Dave Hansen <dave.hansen@xxxxxxxxx>
    Reported-by: syzbot <syzbot+5d1bad8042a8f0e8117a@xxxxxxxxxxxxxxxxxxxxxxxxx>
    Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
    Reviewed-by: Eric Biggers <ebiggers@xxxxxxxxxx>
    Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/arch/x86/crypto/aesni-intel_glue.c b/arch/x86/crypto/aesni-intel_glue.c
index 2144e54a6c89..388643ca2177 100644
--- a/arch/x86/crypto/aesni-intel_glue.c
+++ b/arch/x86/crypto/aesni-intel_glue.c
@@ -849,6 +849,8 @@ static int xts_crypt(struct skcipher_request *req, bool encrypt)
 		return -EINVAL;
 
 	err = skcipher_walk_virt(&walk, req, false);
+	if (err)
+		return err;
 
 	if (unlikely(tail > 0 && walk.nbytes < walk.total)) {
 		int blocks = DIV_ROUND_UP(req->cryptlen, AES_BLOCK_SIZE) - 2;
@@ -862,7 +864,10 @@ static int xts_crypt(struct skcipher_request *req, bool encrypt)
 		skcipher_request_set_crypt(&subreq, req->src, req->dst,
 					   blocks * AES_BLOCK_SIZE, req->iv);
 		req = &subreq;
+
 		err = skcipher_walk_virt(&walk, req, false);
+		if (err)
+			return err;
 	} else {
 		tail = 0;
 	}